Rotary drilling apparatus



Patented Jan. 2l, 1936 UNITED STATES EATENT OFFICE 2,028,478 ROTARYDRILLING APPARATUS Levyn Ray Schuessler, St. Louis, Mo. ApplicationAugust 8, 1934, Serial No. 738,943 6 claims. (o1. c55-2s) This inventionrelates generally to drilling apparatus, .and more specifically torotary drilling apparatus intended for use in drilling oil wells, gaswells, water wells, and other similar earth openings, the predominantobject of the invention being to provide a rotary drilling apparatus ofthe telescopic type which is so constructed and arranged that diierenthydrostatic and physical pressures may be applied to the drill bit atthe will of the operator of the drilling apparatus from the surface ofthe ground, when the drilling operation being performed requires thatthe downward pressure on the drill bit be varied.

Prior to this invention rotary drilling apparatus were produced whichincluded telescopic sections in the drill stems which serve to limit theweight applied to the drill bits. In other words, in the use of atelescopic drill stem of the sort mentioned the drill bit was subjectedto the weight of only the portion of the drill stem which was locatedbelow the telescopic section of the drill stem, hence in the case ofvery deep wells the drill bits were not subjected to the enormous weightof the entire Vdrill stem which might cause the drill bits to be quicklydulled or even crushed.

The telescopic drilling apparatus referred to were capable of reasonablyeilicient use, but in such .apparatus a serious deficiency was presentthat prevented the drilling apparatus from attaining the higheii'lciency desired for it. This deficiency resided in the fact that itwas not posf sible to vary the pressure to which the drill bit wassubjected during a drilling operation. In other words, in the use of thetelescopic drill stems heretofore known the pressure on the drill bitwas positively fixed by the Weight of the portion of the drill stembelow the telescopic section and this pressure could not be variedexcept by pulling the drill stem and adding length to the lower portionthereofy or by lowering the portion of the drill stem located above thetelescopic section and imposing the additional weight thereof on thedrill bit.

The main object of the present invention is to provide a telescopicrotary drilling apparatus which is so constructed and arranged that thedownward pressure exerted against the drill bit may be varied withincertain limits at all times at the will of the operator of the apparatusand from the surface of the ground. This regulation of the pressure onthe drill bit is obtained by controlling the flow of fluid which passesthrough the improved rotary drilling apparatus in a manner to increaseor decrease the pressure of the fluid at a certain point within thedrilling apparatus. A portion of the drilling .apparatus which isdirectly associated with the drill bit is subjected to the varyingpressures of the iiuid, withv the result that the downward pressure onthe drill bit is likewise Varied.

Fig. 1 is a fragmentary rvertical section of a drilling apparatusconstructed in accordance with this invention.

Fig. 2 is a View similar to Fig. 1, but showing the parts of theapparatus in dilerent positions. `1l) Fig. 3 is an enlargedcross-section taken on line 3 3 of Fig. 1.

In the'drawing, where is shown for the purpose of illustration, merely,one embodiment of the invention, A designates a portion of a drill stem15 made in accordance with this: invention. The drill stem' A includesan upper section B, a lower section C, and an intermediate section Dwhich provides the drill stem with a telescopic joint, said sections B,C,vand D being of tubular formation. 2o The upper sectionB is ofconsiderably less diameter than the intermediate section D, and saidupper section is extended into said intermediate section as shown inFig. 1, said sectionsB and D being capable of telescoping movementrelative 25 to each other. v l

At the inner face of the intermediate section D vand at the outer faceof the upper section B cooperating ribs I and 2 are formed, as shown inFig. 2, which abut with each other in a manner to prevent relativerotary movement between said sections while permitting free longitudinalmovement of said sections with respect to each other. The ribs may beformed integrally with said sections B and D, or, if desired, they maybe in the form of separate elements secured to the section in anysuitable manner. The ribs l formed at the inner face of the intermediatesection D extend continuously from a point near the upper end of saidintermediate section to a point near the lower end thereof, while theribs 2 formed at the outer face of the upper section B extend upwardlyfrom the lower end of said upper sectiona slight i, distance. 'Iheintermediate section D has fixed at its inner face a ring 3 which actsas a stop for 45 limiting outward movement of the upper section B andthe intermediate section D with respect to eachother, the shoulders 2 atthe upper ends of the ribs 2 contacting with the lower edge of the'ring3 when the limit of outward movement 50 of the sections B and D has beenreached. At its upper end the intermediate section D is provided with aninternally screw-threaded portion 4 which receives an externallyscrew-threaded gland 5, andV suitable packing 6V is interposed 55 Cilime'diate shank .portion 9b.

between the lower end of the gland 5 and the upper end of the ring 3 toprevent a leakage of mud-laden fluid between the contacting walls of thesections B and D.

At the lower end of the intermediate sections A a fluid-controllingelement l is located. This fluid-controlling element comprises a baseportion B through which a fluid passageway 8' is formed, saidfluid-controlling element being secured to the intermediate section A byhaving its externally screw-threaded base portion 8 screwed into thelower internally screw-threaded end portion of sai-d intermediatesection. The fluid-controlling element includes an upwardly extendedshank 9 which is divided into portions of Varying diameters, the shankportion .ll'f1 vwhich is located immediately adjacent to the baseportion 8 being of greater diameter than the intermediate shank portion9b, and the outer shank portion 9C being of less diameter than theinter- At the point .where :theshank portions 9|a and leb join eachother a `flat face .l0 iszprovided, and at the point'wherethefshankportions 9b; and '9 join eachother a similar flat face ll islocated. Also, the outer lend of `the shank portion VVVil" is providedwith a 'flat facell. Theflat faces lll, Il, and ll' are disposed atsubstantial right angles with respect 'toithe'major axis of the shank 9of the fluidcontrolling-'element 21. The fluid passageway 8' `formedthrough the base portion' of the'fluidcontrolling element is providedwith openings at the lpoint where the base portion joins lthe `Ishank9a.

l"The particular structure Vshown in the drawing includes a coupler. l2which'serves to connect the 'intermediate-section D of the drill stem tothe lower lsection-C thereof This coupler is pro- Evidedwithiscrew-threaded portions which' engage screw-threaded-portions ofsaid intermediate and `lower sectionsandfthus connects said sectionsitogether.

TIn the use of a rotary drilling apparatus of the L.type-:disclosedyherein muda-laden 'fluid is forced downwardly* through the-'drill stemby a suitable pump (not shown) located at the surface of the fground,and this fluid passes through fluid disycharge-apertures 'formed in thedrill bit for the purpose of 'lubricating `the drill bit and washingawaythe cuttings while it is performing the drill- 'fing operation. Themud-laden fluidfis returned -to `the pump byibeing 'forced therebyupwardly through `the hole being drilled between the wallof'saidholean'd the outer face of the drill stem.

'Whentheimproved drilling apparatus disclosed :herein isbeingusedonlythe weight of the lower section'C of the drill 4stem-.is imposedon the drill :bit because of the :presence of the telescopic joint .insaid drill stem, and due to the fact that 4.this weight plus thedownwardexertion produced :by movement of :the fluid against the faces lll, I l,andi-I" providessufiicient downward pressure on thedrillzbit to 'causeit to cutthrough strata of 'ordinary hardness'encountered by the drillbit,

"the `drilling will progress 'in a uniform manner,

the upper Vsection of the drill stem being fed `downwardly inVaccordance lwith the downward ;movement ofthedrill bit and the lowerdrill stem section, so as to maintain the'telescopic `sectionsoftheldrillstem in substantially the same'relative lpositions during the-drilling operation. `During -such'drilling'operation the lower end'por-.tlonof Ithe 'upper section B of the drill-stem is maintained-inanelevated position withrespect to theshank 9 ofthe fluid-controllingelement 'Las Vlower .l end of the rupper Vstillgreater choking effect isshown in Fig. 1, so that the mud-laden fluid may pass through the drillstem in an entirely unrestricted manner.

Assume, however, that instead of encountering strata of ordinaryhardness the drill bit encounters a stratum w "ch, because of unusualhardness or for some other reason, is not readily penetrated by thedrill bit. In this event the operator will lower the upper drill stemsection until the shank S of the fluid-controlling element 'I isextended into the lower end portion of said upper drill stem section.This will have the `effect of choking the lower end portion of the upperdrill stem section so as to restrict the passage of mud-laden uidtherethrough. Also, the

degree of choking effect obtained may be regulated by positioning thelower end of the upper drillstem section adjacent to the differentportions a, 9b, and 9 of the shank of the fluid-controlling element duesaid portions'a, 9b, and 90. In other words, if the ydrill stem sectionwere located adjacent to the shank portion 9c a certain chokingv effectwould be obtained, while a greater choking I.effect would be obtained ifthe lower end'of'the upper drill stem section were located adjacenttothe shank portion 9b. Likewise, a obtained when the lower end of theupper drill stem section is located adjacent to the shank portion 9a.

'.When the up-per drill stem action is lowered as describ-ed to causeone of the portions 9a, 9b, or 9C of the shank l to be located withinthe lower end of said upper drill stem section, the

fiow'of mud-laden fluid is restricted at the lower end of the upperdrill stem section, and because the pump continues to deliver fluid tothe upper drill stem section thepressure of the fluid therein will `beincreased. This increased pressure acts-against the flatfaces-of theshank "9 (the faces Ill-and Il, andthe face Il at'the outer en`d of theshank portionSc) in a manner to Vforce the intermediate section D andthe'lower section Cfof the'drill stem, togetherwith the drill bit,downwardly downward pressure `on the 'drill bit is fprovided. It isimportant to note that various additional downwardly vworking pressureson the "drill bit maybe obtained `by positioning the lower end ofthe-upperrdrill stem section adjacent the different shank portions921,9", and 9C, for it is plain that greater fluid pressure is built upin the upper drill stem section when'the choking effect at `the lowerend thereof is increased by the use of a shank portion of increaseddiameter, while such uadditional kfluid pressure is less when a `shankportion of smaller diameter is vused for choking purposes.

The flat faces lil, Ii, and Il of the shank 9 of the fluid-controllingelement 'l serve also as impact Afaces against which the flowingmudladen iluidmoves. This movement of the mudladen fluid .against theflat faces mentioned tendsto force thedrill bit downwardly and thusapply additional downward pressure thereagainst.

It is important to note that when the drill stem is entirely telescopedthe'fiow of mud-'laden fluid is not entirely stopped. In other words,regardless of the Vrelative positions 'of the telescoped elements ofthedrill 4stem,.a flow of 'fluid through the drill stern is maintainedat all'times.

In this connection attention is directed to Fig. 2, wherein the upperdrill stem section B is shown as Supportedbythe shoulder 8a vat rthe tothe different diameter of f whereby the Irequired additionalvVlan-member is restricted and the pressure of top of the base of thefluid-controlling element -When so positioned it is plain that theentire weight of the upper drill stem section is imposed on the drillbit and the drill stem may be used in the manner of an ordinarynon-telescopic drill stem. When the drill stem is so used the mudladenfluid may flow freely through the drill stem, due to the fact that theinner face of the lower portion of the upper drill stem section is cutaway, as indicated at B', to provide space for such free passage offluid through the drill stem when the telescopic drill stem is entirelycollapsed. This cutaway portion B does not extend to the lower end ofthe upper drill stem section, hence the choking effect heretoforedescribed is obtained.

Also additional downward pressure may be applied to the drill bit of myimproved apparatus by maintaining the telescopic members of the drillstem in the approximate positions in which they are shown in Fig. 1 andincreasing the pressure produced in the iluid by the pump by stepping upthe pump. In this event the Vincreased pressure acting against the facesIU, H,

and Il' will exert downwardY pressure on the drill bit.

It is obvious, therefore, that the improved apparatus may be operated sothat only the weight of the lower drill stem section plus the downwardpressure produced by the mud-laden fluid moving against the faces I 0,II, and l I is imposed upon the drill bit, and if desired the weight ofthe lower drill stem section may be partially supported from the derrickto lessen its weight on the drill bit. Also this downward exertionagainst the drill bit may be increased by choking the flow of fluid atthe lower end of the upper drill stem section as already explainedherein, so as to exert additional fluid pressure against the faces I B,Il, and l I. Additionally, the upper drill stem section may be loweredso that its weight is imposed on the drill bit, .and if desired thisadditional weight may be balanced from above the ground so that theentire weight of the upper drill stem section or a portion thereof maybe imposed on the drill bit. Finally, additional fluid pressure may beapplied to the drill bit by increasing the fluid pressure produced bythe pump and causing this additional pressure to act against the facesof l0,||,and|l'.

Thus it is plain that my improved apparatus is capable of very flexibleuse and practically any desired downward pressure may be applied to thedrill bit.

In addition to the flat faces I0, H, and Il' on the shank of thefluid-controlling element 1 I provide a similar flat face I which islocated between the base portion 8 and the shank portion 9a.

I claim:

1. A drill stem comprising a pair of tubular members arranged intelescopic relation, means to restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for'fluidformed through said tubular members, a fluid-controlling element, saidhuid-controlling element being supported by one of said tubular membersand having a shank portion relative to which an open end ofthe other ofsaid tubular members moves in a manner to cause said shank portion to beextended into said open end of said other tubular member and partiallychoke same, whereby passage of fluid through the open end of said othertubufluid adjacent to the open end of said other tubular'memberisincreased, a pressure-receiving face formed on said shankportion andmovable into and out of said open end of said other tubular memberagainst which said increased fluid lpressure acts to move saidfluid-controlling element downwardly, and a drill ,bit to which istransmitted downward movement imparted by said increased fluid pressureto said fluid-controlling element.

2. A drill stem comprising a pair of tubular members arranged intelescopic relation, 'means to restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for fluidformed through said tubular members, a fluid-controlling element, saidfluid-controlling element being supported by one of said tubular membersand having a shank portion relative to which an open end of the othero-f said tubular members moves in a manner to cause saidshank portion tobe extended into said open end of said other tubular member andpartially choke same, whereby passage of fluid through the open end ofsaid other tubular member is restricted and the pressure of fluidadjacent to the open end of said other tubular member is increased, apressure-receiving face formed on said shank portion and movable intoand out of said open end of said other tubular member against which saidincreased fluid pressurel acts to move said fluid-controlling elementdownwardly, said pressure-receiving face being disposed at anapproximate right angle relative to the major axis of said shankportion, and a drill bit to which is transmitted downward movementimparted by said increasedrfluid pressure to said fluid-controllingelement.

3. A drill stem comprising a pair of tubular members arranged intelescopic relation, means to restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for fluidformed through said tubular members, a fluid-controlling element, saidfluid-controlling element being supported by one of said tubular membersand having a shank p0rtion of varying diameters relative to which anopen end of the other of said tubular members moves in a manner to causesaid shankv portion to be extended into said open end of said othertubular member and partially choke same, whereby passage of fluidthrough the open end of said other tubular member is restricted-and thepressure of fluid adjacent to the open end of said other tubular memberis increased, pressurereceiving faces formed on said shank portionv andmovable into and out of said open end of said other tubular memberagainst which said increased iluid pressure acts to move saidfluidcontrolling element downwardly, and a drill bit to which istransmitted downward movement imparted by said increased fluid pressureto said l fluid-controlling element.

4. A drill stem comprising a pair of tubular members arranged intelescopic relation, means to restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for fluidformed through said tubular members, a fluid-controlling element, saidfluid-controlling element being supported by one of said tubular membersand having a shank portion relative to which an open end of the other ofsaid tubular members moves in a manner to cause said shank portion to beextended into said open end of said other tubular member and partiallychoke same, whereby passage of fluid through the open end of said othertubular member is restricted and the pressure of uid adjacent to theopen end of said other tubular member is increased, said shank portionbeing provided with a plurality of portions of different diameters,pressure-receiving faces formed on said shank portion and movable intoand out of said open end of said other tubular member against which saidincreased fluid pressure acts to move said fluid-controlling elementdownwardly, and a drill bit to which is transmitted downward movementimparted by said increased uid pressure to said fluid-controllingelement.

5. A drill stern comprising a pair of tubular members arranged intelescopic relation, means te restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for fluidformed through said tubular members, a fluid-controlling element, saidduid-controlling element being supported by one of said tubular membersand having a shank portion relative to which an open end of the other ofsaid tubular members moves in a manner to cause said shank portion to beextended into said open end of said other tubular member and partiallychoke same, whereby passage of fluid through the open end of said othertubular member is restricted and the pressure of fluid adjacent to theopen end of said other tubular member is increased, said shank portionbeing provided with a plurality of portions 'of different diameters, andflat pressure-receiving faces arranged at the junctions of saidplurality of portions and at the outer end of said shank portion andmovable into and out of said open end of said other tubular memberagainst which said increased fluid pressure acts to move saidfluidcontrolling element downwardly, and a drill bit to which istransmitted downward movement imparted by said increased fluid pressureto said fluid-controlling element.

6. A drill stem comprising a pair of tubular members arranged intelescopic relation, means to restrict rotary movement of said tubularmembers with respect to each other, communicating passageways for fluidformed through said tubular members, a fluid-controlling element, saiduid-controlling element being supported by one of said tubular membersand having a shank portion relative to which an open end of the other ofsaid tubular members moves in a manner to cause said shank portion to beextended into said open end of said other tubular member and partiallychoke same, whereby passage of fluid through the open end of said othertubular member is restricted and the pressure of fluid adjacent to theopen end of said other tubular member is increased, said shank portionbeing provided with a plurality of portions of different diameters, andfiat pressure-receiving faces arranged at the junctions of saidplurality of portions and at the outer end of said shank portion andmovable into and out oi said open end of said other tubular memberagainst which said increased fluid pressure acts to move saidfluidcontrolling element downwardly, said fluid-controlling elementhaving a fluid passageway formed through a portion thereof, and a drillbit to which is transmitted downward movement imparted by said increaseduid pressure to said fluid-controlling element.

LEVYN RAY SCHUESSLER.

